线性菲涅耳集热器接收器对镜场的遮挡研究

带有二次反射器的线性菲涅耳聚光集热器，虽然其接收器表面的能量分布更均匀，但也增加了接收器对反射镜场的遮挡。本文采用理论计算和模拟两种方式对已设计的线性菲涅耳集热器二次反射器对镜场的遮挡情况进行分析，先通过理论计算得出二次反射器对西边三块初级反射镜遮挡角θni的范围，然后利用光线追踪软件模拟出安装和不安装二次反射器两种情况下到达初级反射镜的光线数目，根据光线数目变化情况得出西边三块反射镜的遮挡角变化范围分别为70º ~ 90º、54º ~ 72º和42º ~ 58º，同时引入光线损失率来衡量二次反射镜对镜元遮挡的影响，结果得出安装二次反射器后镜元光线损失率最大值达到23.53%。

Discussion of Mirror Field Shelter from Linear Fresnel Collector Receiver

The linear fresnel reflector (LFR) with secondary reflector has more uniform solar radiation distribution on the receiver surface, but it increases shelter between receiver and reflector. In this article, the shielding of the designed LFR with secondary reflector was analyzed by theoretical calculation and simulation. Firstly, the range of shielding angle θni between second reflector and the west three primary mirrors was obtained by theoretical calculation. Then, the number of received rays of primary mirrors was simulated by using the ray-tracing with or without the installation of secondary reflector. According to the change of numbers, it showed that the range of shielding angle of west three mirrors were 70º ~ 90º, 54º ~ 72º and 42º ~ 58º, respectively. In addition, loss rate of rays was used to evaluate the shielding effect of secondary reflector, it showed that the maximum loss rate of rays was 23.35% with the secondary reflector.